Most ovarian cancer is not diagnosed until the disease has reached an advanced stage because the early stage disease is typically non-symptomatic. When diagnosed, extensive intra-abdominal metastases have often developed in the peritoneum. Standard treatment includes a surgical cytoreduction to remove the bulk tumor and a follow-up platinum-based chemotherapy regimen. Despite the successful primary treatment, unfortunately, 80?90% of women will experience recurrence of tumors. During the procedure, if all cancerous tissues could be removed, the chance of having an extended disease-free period or even a cure is high. However, some cancerous tissues are not apparent to naked-eye surveillance, hence the surgical outcome can vary. A sensitive and specific dye which could highlight the micro-cancerous tissues would be extremely helpful in minimizing the undesired oversight of leaving cancerous tissue behind and result in a better outcome. In this application, based on our recent finding, we are proposing to develop a sprayable, prompt color changing agent to highlight cancerous tissues with clarity, sensitivity, and specificity. The key component of the proposed cancer highlighter is a fluorogenic near-infrared sensitive dye, which is non-fluorescent in normal tissues but is instantly brightly fluorescent when it is absorbed by the cancer tissues. The cancer selective staining capability of this product will make the surgical procedure precise and effective, as well as make the early identification of recurrence possible.